A 72-year-old male with a known history of chronic obstructive airway disease had eight admissions to hospital with a cough and breathlessness over a 12-month period. He had stopped smoking two years previously. His normal exercise capacity was limited to 27.5 metres on the flat before stopping. He was taking salmeterol, pulmicort and oxivent inhalers, and had received several courses of steroids in the past year. On examination he was cyanosed. His heart rate was 100 beats/min and regular. His blood pressure measured 110/70 mmHg. The JVP was raised 4 cm above the costal margin at 45°. The trachea was central. Chest expansion was generally reduced. Percussion note was hyper-resonant and on auscultation of the lungs there was generalized reduction of air entry throughout. Both heart sounds were soft but there were no added heart sounds or murmurs. Investigations are shown.
Hb 19 g/dl PCV 0.56 l/l WCC 8 109/l Platelets 340 109/l MCV 82 fl Chest X-ray Hyper-inflated lung fields Arterial blood gases: pH 7.35 PaO2 7.5 kPa PaCO2 6.1 kPa Bicarbonate 34 mmol/l Echocardiography Normal left ventricle. Right ventricular hypertrophy and dilatation Pulmonary artery pressure of 42 mmHg
Which treatment is most useful for long-term survival?
a. Oral aminophylline.
b. Diuretic therapy.
c. Regular venesection.
d. High-dose steroids.
e. Long-term oxygen therapy.
Answer:
Indications for long-term oxygen therapy are a PO2 of 7.3–8 kPa once stable and either secondary polycy thaemia, nocturnal hypoxaemia, peripheral oedema or pulmonary hypertension. The patient in question fulfils the criteria. Other patients for whom long-term oxygen therapy may be considered include those who have normal oxygen saturation at rest but desaturate on exercise, and those in whom exercise capacity is improved with oxygen therapy.